[clang] [llvm] [IR] Allow fast math flags on calls with homogeneous FP struct types (PR #110506)

[Benjamin Maxwell via cfe-commits]

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@@ -326,6 +326,21 @@ class FPMathOperator : public Operator {
   /// precision.
   float getFPAccuracy() const;
 
+  /// Returns true if `Ty` is a supported floating-point type for phi, select,
+  /// or call FPMathOperators.
+  static bool isSupportedFloatingPointType(Type *Ty) {
+    if (auto *StructTy = dyn_cast<StructType>(Ty)) {
+      if (!StructTy->isLiteral() || !StructTy->containsHomogeneousTypes())
+        return false;
+      Ty = StructTy->elements().front();
+    } else if (auto *ArrayTy = dyn_cast<ArrayType>(Ty)) {
+      do {
+        Ty = ArrayTy->getElementType();
+      } while ((ArrayTy = dyn_cast<ArrayType>(Ty)));
+    }
+    return Ty->isFPOrFPVectorTy();
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MacDue wrote:

Done :+1: 

https://github.com/llvm/llvm-project/pull/110506